The present invention relates to a system for the transmission of high-definition television pictures via a narrow passband channel, the system comprising a transmission part formed by an arrangement for providing said pictures which are constituted by a plurality of picture elements or samples distributed over even and odd lines, a filter member for filtering said samples, a sampling circuit for taking certain samples from the output of the filter member and a transmission circuit for transmitting said samples via the channel, also at least one receiving part formed by a receiving circuit for receiving said samples, an interpolation member for recovering samples on the basis of received samples and a first display circuit for converting the recovered samples into a restored high-definition picture.
The present invention also relates to a transmitter and a receiver suitable for the system.
Systems of this type are well known and are used with great advantage more specifically in the transmission of high-definition pictures which are compatible with the "MAC" standards, more particularly the "D2-MAC" standard (recommendation 601 of the C.C.I.R).
A prior art system of this type is described in the article "A SINGLE CHANNEL HDTV BROADCAST SYSTEM--THE MUSE--" by Yuichi Ninomiya et al, published in the periodical "NHK LABORATORIES NOTE", vol. 304 of September 1984. This MUSE system, which is not adapted to said procedures, can easily be rendered suitable for these procedures by linearly modifying its characteristic parameters. This known system utilizes, for the transmission of the samples of a picture, a sampling structure which extends over four fields. Picture elements belonging to different spatial positions are transmitted in these four consective fields. When the processed picture, is a still picture a good quality is obtained. On the other hand, the transmission in four fields does not render it possible to obtain a good quality for the recovery of moving pictures in which portions move perceptibly during four consecutive fields.